Installation of Automatic SeismicTrip System in Existing NPPs

Prepared by: Ting ChowPresented by: Lih-Yih Liao

Institute of Nuclear Energy Research (INER)Taiwan, ROC

Third TAEC-USNRC Technical ExchanTAECtingNRC, Washington D.C., USA

May 31, 2005

11

Contents

BackgroundApproachASTS design logicMajor elements in the ASTS ASTS installationMajor dedication processConclusion

22

Background

Taiwan island is located at a complex juncture between the Eurasian plate and Philippine sea plateIt was the disastrous Ji-Ji earthquake(M=7.3) occurred on September 21, 2000 triggered TAEC to suggest TPC to install the ASTS in its 6 existing nuclear units to further ensure the safety.ASTS is mandatory in Japan, but not in US..

33

Approach

Technical requirements in the purchase specification was prepared by the TPC and approved by the TAEC.Foxboro/Invensys design/product plus INER dedication process.Use plant’s RPS trip logic

44

Trip wiring for TPC NPP1,2 (OR logic)

Wiring for NPP1 (OR Logic)

A1/ a NO/To RPS AA`1/ a

NO/To RPS B

NO/To RPS C

NO/To RPS D

A`

A

B D

C

B` D`

C`

Upper Floor

Lower Floor

Location of Accelerometers Set point and Trip Unit

B1/ a B`1/ a

C1/ a C`1/ a

D1/ a D`1/ a

55

Trip wiring for TPC NPP3 (OR logic)

SSPS2/3

LOGIC

SSPS2/3

LOGIC

TRIP Train-A

TRIP Train-B

A

C

B

66

FBA-23

BPF V/A Converter

Y

設定點跳脫次單元Foxboro SPEC 200 (Class 1E)

X

Z

訊號處理次單元0.1 to 10Hz BPF ＋Volt/Amp Converter

(To Be Dedicated)

測震感測器次單元

2AP-A

LM

2AP-A

LM

2AI-I2V

2AI-I2V

N-

2AX

+PS9A

N-2A

O-L

2C-R

Blank

SPEC200 NEST (N-2ANU-P)

DC 24V

Trip指示燈

DC 24V

RPS Logic

強震急停裝置跳脫邏輯測試平台架構圖

4-20 mA±2.5V

BPF V/A Converter

BPF V/A Converter

0~5V

BPF V/A Converter

Y X

Z ±2.5V

BPF V/A Converter

BPF V/A Converter

0~5V

±12V

FBA-23

±12V

N-2A

P+TIM

2AP-A

LM

2AP-A

LM

2AI-I2V

2AI-I2V N

-2A

X+P

S9A

N-2A

O-L2C

-R

Blank

SPEC200 NEST (N-2ANU-P)

DC 24V

4-20 mA

N-2A

P+TIM

Seismic sensor

ASTS design logic

77

Major elements in the ASTS

There are three sub-units in the ASTS:--Earthquake sensors:

Kinemetrices FBA23 triaxial accelerometers.

--Data process:BPF( up to10hz), B/U converter , V/A converterThese two sub units are installed in one water-proof rigid box (sensor box)

-- Trip control module:Foxboro spec200 module(with some modification),

and two spec200 are installed in one 19” control cabinet

88

ASTS installation

Install seismic sensors (FBA23) on both basematfloor and operating floor in major (reactor/auxiliary) building for BWR/PWR.The number of seismic sensors on each floor depends on plant’s RPS trip logic, i.E.,4/floor for BWR and 3/floor for PWR. Total 44 sensors installed in 6 operationg units.One control cabinet responsible for two sensor boxes. Total 22 control cabinets installed in back panel rooms in control buildings.

99

Major dedication process

NEMA4 water proof testAnti-radiation test: 8.76x100 rads over 40 yearsEMI/EMC test: follow RG 1.180 requirement

1010

Major dedication process

Seismic test: use plant specific required response spectrum, TRS envelop RRS Seismic auto-trip accuracy test: must not trip when filtered PA below set point minus 0.05g, and must trip when filtered PA exceeds set point over 0.05g.Trip signals occurred within 10 second interval are considered as same events

1111

2 3 5 2 3 5 2 3 50.1 1.0 10.0Frequency, Hz

0.00

0.40

0.80

1.20

1.60

Spec

tral A

ccel

erat

ion,

g

OBENPS I, +0.83ft Horizontal

NPS I, +0.83ft Vertical

NPS I, +56.83ft Horizontal

NPS I, +56.83ft Vertical

NPS II, -42.5ft Horizontal

NPS II, -42.5ft Vertical

NPS II, +2.17ft Horizontal

NPS II, +2.17ft Vertical

NPS III, +74&80ft Horizontal

NPS III, +74&80ft Vertical

NPS III, +126ft Horizontal

NPS III, +126ft Vertical Zone2

OBE RRS

Damping ratio = 5 %

2 3 5 2 3 5 2 3 50.1 1.0 10.0Frequency, Hz

0.00

1.00

2.00

3.00

Spec

tral A

ccel

erat

ion,

g

SSENPS I, +0.83ft Horizontal

NPS I, +0.83ft Vertical

NPS I, +56.83ft Horizontal

NPS I, +56.83ft Vertical

NPS II, -42.5ft Horizontal

NPS II, -42.5ft Vertical

NPS II, +2.17ft Horizontal

NPS II, +2.17ft Vertical

NPS III, +74&80ft Horizontal

NPS III, +74&80ft Vertical

NPS III, +126ft Horizontal

NPS III, +126ft Vertical Zone2

SSE RRSDamping ratio = 5 %

OBE RRS (envelope all floor RS) SSE RRS(envelope all floor RS)

OBE/SSE required response spectrum

1212 Sensor Box Seismic Test

1313Controller Rack Seismic Test

1414

Example of SSE TRS vs RRS

Example of OBE TRS vs RRS

TRS envelopes RRS

1515Trip Setting Accuracy Test

1616

Conclusion

This total 2,500,000.-USD project finished in 1 year.The important features of the ASTS include: Foxboro spec200 analog system(10 seconds timer card, 20ms trespassing time needed for relay to seal-in), low pass filter, and use pa(low-pass filtered) for auto trip parameter.Independent dedication process performed by INER

1717

Historical Earthquakes

This map showed all felt earthquakes and major disastrous earthquakes ever struck Taiwan since 1900. It is noted that there are five in-land earthquakes with magnitude larger than 7.0 and these are those cause high fatalities

1818

Tectonic plates of Taiwan islandThis map showed the tectonic plates of Taiwan Island (After Angelier, 1986). Basically Taiwan is on the boundary between Eurasian Continental Plate and Philippine Sea Plate. Due to the process of collision of these two plates, eastern part of Taiwan moves toward NW at a rate about 2.5~8.0 cm/year based on actual GPS measurement starting from 1993.

1919

Sensor Box

2020Spec 200 controller cabinet

21

Sensor box and ASTS control cabinet